P Peterson 1 , SV Fowler 2 , M Merrett 3 and P Barrett 4 1 LCR, PN, 2 LCR, Chch, 3 The Open Polytechnic of NZ, Lower

1. Heather beetle impact assessment P Peterson1, SV Fowler2, M Merrett3 and P Barrett4 1LCR, PN, 2LCR, Chch, 3The Open Polytechnic of NZ, Lower Hutt, 4Massey University, PN

2. Heather (Calluna vulgaris)

3. Spreading • - Te Aroha • - Rotorua • Tarawera • Pureora • Mt Egmont National Park • Hokitika • Mt Cook • Queenstown • Te Anau · · · · · · · · · ·

10. Heather beetle (Lochmaea suturalis) Photo by Shaun Forgie

11. Impact assessment

12. Assessment area

13. Beetle vs herbicide Treatments: Herbicide (2,4-D ester) Heather beetle Control Design: 3 treatments 4 blocks 2 reps per block

14. Vegetation cover • Pre-treatment • 50 x 50 cm Merilyn Merrett estimating vegetation cover

15. 37 vascular common • 25 dicot species • 20 native • 5 exotic • 12 monocot species • 8 native • 4 exotic • 9 vascular uncommon • Native and exotic, i.e. sedges, lilies, grasses, etc. 37 vascular species

16. Applied treatments

17. Beetle vs herbicide • No beetle establishment • Herbicide impacts were interesting

18. Herbicide only assessment 2002–2011 Before and after photos

19. Control 2002 2011 Herbicide

20. Heather (Calluna vulgaris)

22. Native dicotyledons Sprawling coprosma (C.cheesemanii) Monoao (Dracophyllum subulatum) Tauhinu (Ozothamnus leptophylla) Mountain heath (Pentachondra pumila)

24. Hawkweed (Pilosella officinarum)

26. All monocotyledons Red tussock (Chionochloa rubra) Silver tussock (Poa cita) Yorkshire fog (Holcus lanatus) Browntop (Agrostis capillaris)

28. Red tussock (Chionochloa rubra)

30. Browntop (Agrostis capillaris)

32. Summary (herbicide only assessment) • Four herbicide applications kill 80% of heather but signs of recovery 4 years later • Heather may recover faster than dicot natives? • Monocot cover (both native and exotic) increases following herbicide application • Heather cover doubled in 9 years if nothing was done

33. Summary (herbicide only assessment) • Four herbicide applications kill 80% of heather but signs of recovery 4 years later • Heather may recover faster than dicot natives? • Monocot cover (both native and exotic) increases following herbicide application • Heather cover doubled in 9 years if nothing was done

34. Summary (herbicide only assessment) • Four herbicide applications kill 80% of heather but signs of recovery 4 years later • Heather may recover faster than dicot natives? • Monocot cover (both native and exotic) increases following herbicide application • Heather cover doubled in 9 years if nothing was done

35. Summary (herbicide only assessment) • Four herbicide applications kill 80% of heather but signs of recovery 4 years later • Heather may recover faster than dicot natives? • Monocot cover (both native and exotic) increases following herbicide application • Heather cover doubled in 9 years if nothing was done

36. But what about the beetles?

37. Difficult to establish Released (1996–2009) 36 000 all stages 78 sites Establishment 9 outbreaks (9%) 2 false starts

38. Impact assessment (beetle vs herbicide – 2nd attempt)

39. Assessment area

40. Beetle vs herbicide Beetle feeding damage visible in 2007

41. Small heather beetle outbreak 2007

42. Plots set up outside beetle-damaged area 2007

43. 4 treatments, 6 blocks assigned 2007 H I H+I

44. Predicted beetle dispersal 2007– ? H I H+I

45. Vegetation cover • Pre-treatment • 50 x 50 cm Merilyn Merrett estimating vegetation cover

46. 32 vascular common • 25 dicot species • 21 native • 4 exotic • 7 monocot species • 5 native • 2 exotic • 15 vascular uncommon • Native and exotic, i.e. sedges, lilies, orchids, grasses, etc. 32 vascular species

47. Applied treatments

49. 2008

50. 2009